With the question on top and explain

658 = 3.14 * r^2 

658 / 3.14 = r^2 

209.55 = r^2 

14.5 = r :)

The major difference is that a histogram is only used to plot the frequency of score occurrences in a continuous data set that has been divided into classes, called bins.  bar charts, on the other hand, can be used for a great deal of other types ofvariables  including  ordinal  andnominal  data sets.